body, html {
    height: 100%;
    margin: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    flex-direction: column;
}

.video-background {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    z-index: -1;
}

.button-container {
    display: flex;
    gap: 20px;
    position: relative;
    z-index: 1;
}

.btn {
    padding: 10px 20px;
    font-size: 18px;
    cursor: pointer;
    border: none;
    border-radius: 50px; /* 椭圆形边框 */
    background: linear-gradient(-45deg, #ee7752, #e73c7e, #23a6d5, #23d5ab);
    background-size: 400% 400%;
    animation: gradientBG 15s ease infinite;
    color: #fff;
    text-decoration: none;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(-45deg, #ee7752, #e73c7e, #23a6d5, #23d5ab);
    background-size: 400% 400%;
    animation: gradientBG 15s ease infinite;
    z-index: -1;
    filter: brightness(150%);
}

.btn:hover {
    color: #000;
}

@keyframes gradientBG {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

/* 响应式设计 */
@media (max-width: 768px) {
    .button-container {
        flex-direction: column;
        gap: 10px;
    }

    .btn {
        padding: 15px 30px;
        font-size: 16px;
    }
}
